Systems and methods for repetitive tuning of matching networks

Abstract

A method for repetitive tuning of a matching network in a radio frequency plasma processing device, the method including detecting a condition within the matching network and determining if the condition is a known condition for the matching network. Also, finding a prior solution and to the condition when the condition is the known condition for the matching network; and replicating the prior solution for the condition in the matching network.

What is claimed is: 
     
       1. A method for repetitive tuning of a matching network in a radio frequency plasma processing device, the method including:
 detecting a condition within the matching network; 
 determining that the condition is a previously resolved condition for the matching network, the previously resolved condition having a prior solution that was learned, during operation of the matching network, and then stored as part of a data set of solutions to previously resolved conditions; 
 obtaining the prior solution to the condition from the stored data set of solutions to previously resolved conditions; and 
 replicating the prior solution for the condition in the matching network. 
 
     
     
       2. The method of  claim 1 , wherein the previously resolved condition is determined using an empirical data set. 
     
     
       3. The method of  claim 2 , wherein the empirical data set comprises current split ratios. 
     
     
       4. The method of  claim 3 , further comprising storing the empirical data in a storage medium accessible by a programmable logic controller that is connected to the matching network. 
     
     
       5. The method of  claim 1 , wherein the prior solution comprises a capacitor position that is tuned to a previously learned impedance point. 
     
     
       6. The method of  claim 1 , wherein the detecting, determining, obtaining, and replicating are automatic when the condition occurs within the matching network. 
     
     
       7. The method of  claim 1 , further comprising determining that the condition does not meet a threshold to determine if the condition is the previously resolved condition for the matching network and discontinuing the method for tuning the matching network. 
     
     
       8. The method of  claim 1 , wherein the replicating the prior solution comprises controlling a capacitor speed based on a percentage of reflected power. 
     
     
       9. The method of  claim 1 , further comprising allowing at least one capacitor to tune with a reflected power at a pre-defined speed. 
     
     
       10. The method of  claim 1 , further comprising recording a capacitor position for the detected condition. 
     
     
       11. The method of  claim 10 , further comprising associating the recorded capacitor position with the prior solution in the stored data set of solutions to previously resolved conditions. 
     
     
       12. The method of  claim 1 , wherein use of the prior solution decreases tuning times in the matching network. 
     
     
       13. The method of  claim 1 , wherein the prior solution prevents capacitor railing during operation. 
     
     
       14. A radio frequency plasma processing device comprising:
 a reaction chamber; 
 a radio frequency generator to supply radio frequency power to a plasma in the reaction chamber; 
 a matching network comprising:
 a matching branch having a first variable capacitor and a second variable capacitor; and 
 a splitter branch having a third variable capacitor and a fourth variable capacitor that are electrically connected to the first variable capacitor and the second variable capacitor; 
 
 an outer coil connected to the third variable capacitor; 
 an inner coil connected to the fourth variable capacitor; and 
 a programmable logic controller connected to the matching network, the programmable logic controller to:
 detect a condition within the matching network; 
 determine if the condition is a known condition for the matching network; 
 find a prior solution to the condition when the condition is the known condition for the matching network; and 
 replicate the prior solution for the condition in the matching network. 
 
 
     
     
       15. The radio frequency plasma processing device of  claim 14 , further comprising a tuning module connected to the matching network, the tuning module to store at least the condition and the prior solution. 
     
     
       16. The radio frequency plasma processing device of  claim 15 , wherein the tuning module stores empirical data comprising transformer coupled capacitively tuning ratios. 
     
     
       17. The radio frequency plasma processing device of  claim 15 , wherein a tuned capacitor position for at least one of the first variable capacitor, the second variable capacitor, the third variable capacitor, and the fourth variable capacitor is recorded and stored by the tuning module. 
     
     
       18. The radio frequency plasma processing device of  claim 14 , wherein the programmable logic controller receives values from at least one sensor associated with at least the third variable capacitor and the fourth variable capacitor. 
     
     
       19. The radio frequency plasma processing device of  claim 14 , wherein a tuned capacitor position for at least one of the first variable capacitor, the second variable capacitor, the third variable capacitor, and the fourth variable capacitor is recorded and stored by the memory module. 
     
     
       20. A non-transitory computer readable medium comprising computer executable instructions stored thereon that, when executed by one or more processing units cause the one or more processing units to:
 detect a condition within the matching network; 
 determine that the condition is a previously resolved condition for the matching network, the previously resolved condition having a prior solution that was learned, during operation of the matching network, and then stored as part of a data set of solutions to previously resolved conditions; 
 obtain the prior solution to the condition from the stored data set of solutions to previously resolved conditions; and 
 replicate the prior solution for the condition in the matching network.